Add tracking back into version tracking (#159)

Samples/Samples/App.xaml.cs

@@ -13,6 +13,8 @@ namespace Samples
         {
             InitializeComponent();
 
+            VersionTracking.Track();
+
             MainPage = new NavigationPage(new HomePage());
         }
 

docs/en/Xamarin.Essentials/VersionTracking.xml

@@ -14,6 +14,24 @@
     <remarks></remarks>
   </Docs>
   <Members>
+    <Member MemberName="Track">
+      <MemberSignature Language="C#" Value="public static void Track ();" />
+      <MemberSignature Language="ILAsm" Value=".method public static hidebysig void Track() cil managed" />
+      <MemberType>Method</MemberType>
+      <AssemblyInfo>
+        <AssemblyVersion>1.0.0.0</AssemblyVersion>
+      </AssemblyInfo>
+      
+      <ReturnValue>
+        <ReturnType>System.Void</ReturnType>
+      </ReturnValue>
+      <Parameters />
+      <Docs>
+        <summary>Starts tracking version information.</summary>
+        <returns></returns>
+        <remarks></remarks>
+      </Docs>
+    </Member>
     <Member MemberName="BuildHistory">
       <MemberSignature Language="C#" Value="public static System.Collections.Generic.IEnumerable&lt;string&gt; BuildHistory { get; }" />
       <MemberSignature Language="ILAsm" Value=".property class System.Collections.Generic.IEnumerable`1&lt;string&gt; BuildHistory" />